Belgian dredging and offshore giant Jan De Nul Group (JDN) is investing in two versatile 6,000-tonne subsea rock installation vessels, ordered from the AVIC Weihai shipyard in China and due for delivery in 2017.
The vessels will not only be able to install rock at depths of up to about 600 m via a flexible fallpipe, but it will also be capable of having cable carrousels installed – along with tensioners, chutes, and auxiliary equipment – for placing cables on the seabed.
“The inclined fallpipe will enable accurate rock installation around structures such as offshore wind turbine foundations and oil and gas platforms,” said a JDN spokeswoman.
“The vessels comply with the IMO Code for Special Purpose Ships and will also act as support for an ROV subsea trencher for cable burial. To enable these functions, the diesel-electric vessels will have DP2 dynamic positioning systems.”
JDN has also taken accommodation seriously, with each vessel having single cabins for up to 60 people, the crew, specialised personnel, and client representatives.
Each vessel will have the following:
Length overall-96 m
Draught loaded-6.5 m
Propulsion power-two x 1,250 kW
Bow thruster power-two x 1,250 kW
Total installed diesel power-6,800 kW
Turntable capacity-4,000 tonnes